Automatic document handler

ABSTRACT

An automatic document handler for supplying documents singly to the platen of a processing apparatus such as a copying machine. Following copying, each document is returned to the document supply where the used documents are kept separated from documents awaiting copying by means of a resettable bail bar. To position the documents properly for copying, the document handler includes a register against which the document trailing edge is abutted through reversal of the platen transport belt. To allow the document to be removed and the platen cleared for the next document, means are provided to remove the register and lower a document deflector into an intercept position, the deflector then serving to guide the document into a predetermined return path back to the document supply without interfering with movement of the next document forward. The platen transport comprises an endless belt conveyor supported for substantially single line contact with the platen surface at a point adjacent to and parallel with the register.

This invention relates to an automatic document handler, and moreparticularly, to an automatic document handler incorporating an improvedtransport for moving documents over the platen surface of a processingmachine.

In handling, automatically, documents, papers, and the like, which areto be processed as by a copying machine, it is usually required that thedocument handling device first separate the document to be copiedhandling device first separate the document to be copied from othersawaiting copying. Following this, the document must be brought intoposition on the machine platen. There, the document is normally locatedin a certain position, or at least within the confines of a given areato assure the making of a complete and visually acceptable copy.

It is clear, therefore, that if, on completion of this process, theentire document is not on the platen, the copy made may be incomplete.Or, if the document is located in a skewed or canted position on theplaten, the copy will reflect, to its detriment, the same skew, or cant.And, if during handling, the original is torn, or creased, the copy willusually bear evidence of this.

On this latter point, it must also be remembered that the original mustalways be handled with care to avoid tearing, creasing, or othermutilation, or damage thereto. This of course is particularly true wherethe original is one of a kind. In summary, therefore, any automaticdevice for handling documents should be capable not only of locating thedocument properly but also of handling the document without damaging thedocument. And later, when copying is completed, the document handlershould clear the document from the platen in preparation for the nextdocument.

From this discussion, it is believed evident that the design andoperation of the platen transport, which serves to move the originalonto and off of the platen, is critical if a successful automaticdocument handler is to be achieved, and problems such as those alludedto earlier are to be avoided.

It is, therefore, a principal object of the present invention to providea new and improved automatic apparatus for handling documents.

It is an object of the present invention to provide an improvedtransport for automatic document handlers especially adapted to carryoriginal documents over the platen glass of a document processingmachine.

It is a further object of the present invention to provide a platentransport for an electrostatic type copying machine adapted to quicklyand reliably move originals into and out of copying position whileavoiding damage or mutilation thereof.

It is an object of the present invention to provide an improvedlow-friction platen transport for the document feeding apparatus of acopying machine.

It is an object of the present invention to provide an improved documenttransport for use with electrostatic type copying machines adapted toavoid or at least reduce the build-up of static electric charges on thedocuments as they are moved into and out of copying position.

It is an object of the present invention to provide an improved documenttransport means for a copying machine arranged to cooperate with adocument registering device to locate the document to be copied in apreset copying position and following copying, to clear the document.

This invention relates to a document handling apparatus for bringingdocuments into copying positon on the platen of a document copyingmachine for copying purposes, the combination comprising, a flexibledocument transport belt; a pair of interior support rolls about whichthe belt is operatively disposed, the support rolls being spaced apartwhereby to provide in cooperation with the transport belt a beltoperating run opposite to and extending across at least a portion of theplaten; means for rotatably supporting each of the rolls so that thesurface of the transport belt therearound is spaced slightly above theplane of the platen surface whereby the operating run of the belt wouldordinarily be spaced above and out of document driving relationship withthe platen; and internal pressure means adapted to force a line of thebelt operating run downward toward the platen into document drivingrelationship with the platen.

Other objects and advantages will appear from the ensuing descriptionand drawings in which:

FIG. 1 is a side view in cross section showing a document handlerincorporating the improved document transport belt of the presentinvention in operative association with a document copying machine;

FIG. 2 is an isometric view of the document handler shown in FIG. 1;

FIG. 3 is an isometric view showing details of the document separatingbail;

FIG. 4 is an isometric view showing the drive details for the maindocument transports of the document handler shown in FIG. 1;

FIG. 5 is an isometric view showing the drive details for the returndocument transports of the document handler shown in FIG. 1;

FIG. 6 is an isometric view showing details of the retard roll drive;

FIG. 7 is a side view in cross section showing details of the documentregister and deflector drive;

FIG. 8 is a top view of the document register and deflector shown inFIG. 7;

FIG. 9 is an enlarged side view showing the improved document transportbelt of the present invention;

FIG. 10 is an isometric view of the document transport belt shown inFIG. 9;

FIG. 11 is an enlarged side view showing details of the cover lockingmechanism for the document handler shown in FIG. 1;

FIG. 12 is a top view of the cover locking mechanism of FIG. 11; and

FIG. 13 is a control schematic for the document handler shown in FIG. 1.

Referring to the drawings, there is shown the document handler,designated generally by the numeral 10 incorporating the platentransport of the present invention. Document handler 10 may be used withany suitable document processing apparatus, such as a copying orreproduction machine 5, which has a platen 6 on which the document to becopied rests.

Document handling apparatus 10 includes a supply tray 12 for storingboth documents 7 to be copied and documents 8 already copied. From tray12, one document at a time is advanced from the bottom of supply 7 by anintermittently operated primary feed roll 14 into the nip of retard rollpair 16, 17. The lower roll 16 is driven in a document feeding directionwhile the upper roll 17 is driven in the reverse or document rejectdirection (as shown by the dotted line arrow in FIG. 1) through asuitable slip coupling which normally enables the lower roll 16 tooverride the reverse drive input to roll 17 and thereby turn roll 17 inthe document feeding direction. However, if two or more documents enterthe nip of roll pair 16, 17, the reduced friction between theoverlapping documents reduces the frictional drive force between rollpair 16, 17, permitting the slip clutch to engage and drive roll 17 inthe reverse, document rejecting direction.

The document emerging from retard roll pair 16, 17 passes into the nipof intermediate roll pair 18, 19, and from there underneath deflectorplate 21 to platen transport 20. Transport 20, which preferablycomprises a belt-type conveyor, first carries the document forward ontoplaten 6 until the entire document is positioned thereon. Transport 20is then reversed to bring the document trailing edge against register22. Register 22 locates the document in copying position following whichthe copy or copies are made by the copying apparatus 5.

When copying is completed, platen transport 20 is again started inreverse to move the document backwards off platen 6, register edge 22being previously retracted for this purpose. Deflector 21, which waspreviously lowered, guides the returning document upwardly into the nipof return roll pair 23. Roll pair 23 move the document along suitablereturn guides 26 through second and third return roll pairs 27, 28respectively, and back into tray 12.

To maintain copied documents which have been designated for convenienceby the numeral 8, segregated from documents 7 awaiting copying, andprevent inadvertent or premature refeeding of the returned documents 8by feed roll 14 following feed of the last one of the documents 7, adisplaceable bail or separator bar 32 is provided. Bail 32 is disposedsubstantially opposite to and above primary feed roll 14 to preventdocuments resting thereon from contacting roll 14. As will appear, bail32 may be reset onto the top of the documents in tray 12 when it isdesired to refeed the documents to copying machine 5.

Referring now to FIGS. 1 and 2, document tray 12 includes asubstantially flat downwardly inclined base 31 and suitable supportingframe 36 carried on copying machine 5 adjacent platen 6. A curved guide33 leads from base 31 to platen 6, which in the arrangement shown issubstantially horizontal. A series of openings 29 in both base 31 andguide 33 accommodate rolls 14, 16 and 18.

As best seen in FIG. 2, a tray assembly 30 is provided for holding thedocuments, the tray assembly being comprised of matching right and lefthand receptacles 41, 41' respectively. Receptacles 41, 41' are arrangedin facing relationship to one another and supported by their lower endson shaft 42, the receptacle supporting segment of which is rectangularin cross section. Shaft 42 is journaled for rotation in bushings 43 onframe 36 adjacent the bottom of base 31. Shaft 42 carries stop collars44 at each end between bushings 43 and cover supports 45, the latterserving to support tray cover 60 from shaft 42 as will appear. Coversupports 45 each include a drive lug 45' adapted, followingpredetermined rotation of the cover 60 in the opening direction toengage a mating shoulder 44' on the adjoining collar 44 and therebydrivingly couple shaft 42 and receptacles 41, 41' thereto.

Receptacles 41, 41' each include a base 46 and outer side 47. The upperportion 47' of receptacle sides 47 are preferably flared outwardly toprovide a slightly enlarged entrance facilitating entry of returningdocuments to the tray assembly 30. The relative narrower sides 47therebelow aid in aligning the document side edges with one another.

Receptacles 41, 41' are preferably supported for lateral adjustingmovement along the rectangular portion of shaft 42 toward and away fromone another to accommodate various size documents. For this purpose, thereceptacles 41, 41' are interconnected adjacent their lower end by meansof cord 48. Cord 48 is supported around pulleys 49 with one terminal endthereof secured to one tray 41 and the other to tray 41'. As can beunderstood, movement of cord 48 effects simultaneous movement of trays41, 41' toward or away from one another.

Suitable detent means (not shown) may be provided to maintain thereceptacles 41, 41' in preselected positions corresponding toconventional document widths. Torsion springs 50 bias receptacles 41,41' inwardly toward base 31 (in the clockwise direction as seen in FIG.1), it being understood that contact between base 31 and the bottom 46of receptacles 41, 41' limits toward movement of receptacles 41, 41'.

To guide returning documents into the receptacles 41, 41' as well asprevent documents from falling out of the receptacles 41, 41',particularly when bail 32 is reset, a cover 60 is provided. Asdescribed, cover 60 is rotatably supported from shaft 42 via supports 45which enable the cover 60 to be swung open for access to the trayassembly 30 during loading and unloading of documents.

Cover 60 includes an exterior wall 62, which may be suitably decorated,depending sides 63, and interior wall 64, which together form a hollowsection or plenum 65. As may be seen in FIG. 2, cover 60 issubstantially rectangular in shape, and sized to overlay the entire base31 including the tray assembly 30. Interior wall 64 of cover 60 issubstantially flush with the top edge of receptacle sides 47 when cover60 is closed, the wall 64 serving as a guide to help route returningdocuments into receptacles 41, 41' as will appear.

A fan 66 is disposed within the cover plenum 65 opposite outlet 67 ininterior wall 64. Fan 66 serves to discharge a low pressure stream ofair downwardly through outlet 67 onto the documents therebelow in trayassembly 30. Fan motor 68 is housed in the cover plenum 65 and suitableair inlet openings (not shown) are provided in the cover proper for fan66.

Cover 60 carries a depending detent and stop member 70 on each sidethereof, stop members 70 being slotted at 71 to receive guide pins 72supported from each side of the frame 36. See FIGS. 11 and 12. Slots 71include an intermediate offset portion 74, offset 74 cooperating withpins 72 to releasably retain cover 60 in a partially open positionsufficient to enable documents to be inserted or removed from the trayassembly. Where further access to the tray assembly 30 is required, pins72 may be released from the offset portions 74, and cover 60 swung opento a maximum open position as defined by the terminal end of slots 71.With such further opening movement of cover 60, shoulders 44', 45' abutto couple shaft 42 with cover 60 so that receptacles 41, 41' aresimultaneously turned outwardly to a substantially vertical position.

To prevent premature or inadvertent opening of door 60 while thedocument handler 10 is operative, a latch mechanism 75 seen best inFIGS. 11 and 12, is provided. Latch mechanism 75 includes a latch 76having a hook end 77 disposed to engage aperture 78 in one of stopmembers 70 to thereby prevent opening of cover 60. Suitable spring means(not shown) biases latch 76 toward the unlatched position. A solenoidoperator 79 is provided having an armature drivingly connected to latch76. Solenoid 79 serves, when energized, to swing latch 76 inwardly intolatching position. In this circumstance, closure of cover 60 engageslatch 76 to prevent reopening thereof until solenoid 79 is deenergized.Solenoid 79 is normally energized during operation of document handler10.

A switch 80 is provided to prevent inadvertent operation of documenthandler 10 whenever cover 60 is open. Switch 80 is disposed foractuation by one stop member 70 with closure of cover 60.

Referring particularly to FIG. 3, the bail 32 is carried by arms 81which are in turn pinned to intermediate links 82. Each link 82 ispivotally supported on the frame 36 through an arm 83. Upstanding framebrackets 36' are provided for this purpose, arm 83 being in effectpinned between brackets 36' and link 82. Intermediate links 82 are alsopinned to crank arms 84 carried by the transversely extending outputshaft 85 of a one revolution clutch 180. As will appear more fullyherein, engagement of clutch 180 turns shaft 85 and crank arms 84through one revolution.

On rotation of crank arms 84, and due to the interrelationship of links82 relative to supporting arms 82, 83, bail 32 moves through a generallyrectangular path, initially in a forward direction generally parallel totray base 31, then up away from base 31, then back toward primary feedroll 14, and then down toward base 31. With reference to any documentsin tray 12 which rest on bail 32, bail 32 moves first forward out fromunder the documents, then raises up to a position above the documents,then moves back to a position above feed roll 14, and then down onto thetopmost document. To provide a predetermined bail pressure, springs 86are provided to bias arms 81 in a downward direction toward tray base31.

A photocell type detector 88 is provided on bail 32. A light 89 fordetector 88 is located under base 31 and opposite detector 88, base 31being suitably apertured for this purpose. As will appear, detector 89responds in certain circumstances to the absence of documents under bail32 to actuate clutch 180 and reset the bail 32 as described heretofore.

To obviate buildup of static electricity on the documents, a suitableion generator 92 is provided adjacent the entrance to the document trayassembly 30. Generator 92, which is connected to a suitable source ofelectrical energy (not shown), serves to ionize the air through whichthe documents returning to tray assembly 30 pass to help neutralize anystatic electric charges that may be on the documents.

Referring now particularly to FIGS. 4-6 of the drawings, a suitabledrive motor 100 is provided. Motor 100 may be conveniently supported onframe 36 below tray base 31. Motor shaft 101 is connected by means oftoothed belt 102 with main power takeoff shaft 103.

The primary feed roll 14, retard roll pair 16, 17, and lower roll 18 ofintermediate roll pair 17, 18 are preferably operated at a lower speedthan that of platen belt 20 and return roll pairs 23, 27, 28. To providesuch low speed drive to rolls 14, 18 and to roll 16 of retard pair 16,17, a toothed belt 104 drivingly connects shaft 103 with clutch 105 ontransfer shaft 106. As will be understood, clutch 105, when actuated,couples power takeoff shaft 103 with transfer shaft 106.

Transfer shaft 106, which is suitably journaled in frame 36, carries adrive pulley 108 on the outside end thereof. A toothed belt 109drivingly connects pulley 108 with gear 110 on shaft 111 of the bottomlimiting roll 16 and with toothed pulley 112 of overrunning clutch 114.Clutch 114 is supported on shaft 115 of the bottom intermediatetransport roll 18 and serves to turn shaft 115 in a document feedingdirection unless the high speed drive input to shaft 115 is operational,during which period clutch 114 overruns as will later appear herein.

Primary feed roll 14 is supported by shaft 118 which in turn is suitablyjournaled in frame 36. Drive belt 117 drivingly connects shaft 118 withlimiting roll support shaft 111. As will be understood therefore,actuation of clutch 105 drives primary feed roll 14, lower retard roll16, and lower intermediate transport roll 18 at low speed in a documentfeeding direction.

Referring now to FIGS. 1, 4 and 5, power takeoff shaft 103 carries adrive pulley 120 on the terminal end thereof. Pulley 120 is connectedwith pulley 121 on stub shaft 122. Gear 123 on pulley 121 meshes withgear 124 on shaft 125 supporting the lower rolls of return transportroll pair 28. A toothed belt 126 drivingly connects shaft 125 with shaft127 supporting the lower rolls of return transport pair 27. A secondbelt 128 drivingly interconnects shaft 125 with shaft 130 supporting thelower rolls of return transport pair 23. The upper rolls of the returntransport roll pairs 23, 27, 28 are supported upon idler shafts 131suitably journaled in return transport sub-frame 36".

Referring particularly to FIGS. 4 and 6, shaft 125 carries a gear 133 onthe end thereof which, in turn, drives, through intermediate gearset134, gear 135 of a hysteresis type clutch 136. Shaft 137 of clutch 136is suitably journaled in transport subframe 36". As seen in FIG. 6, theretard roll 17 is swingably supported by means of arms 17' from theclutch shaft 137. In addition, gear set 138 drivingly couples clutchshaft 137 with the retard roll 17. As will be understood, therefore,engagement of clutch 136 drivingly couples clutch shaft 137 with drivenshaft 125 to turn retard roll 17 via gearset 138 in the reverse ordocument rejecting direction (shown by dotted arrow in FIG. 6).

Hysteresis clutch 136 is preset to engage whenever the reverse torqueapplied to shaft 137 generated through contact of roll 16 with retardroll 17, either directly or through the intermediary of one or moredocuments therebetween, falls below a predetermined level. This normallyoccurs whenever more than one document at a time attempts to passbetween the retard roll pair 16, 17. At other times, clutch 136 iseffectively disengaged and retard roll 17 turns with roll 16 in thedocument feeding direction.

To provide the reversible relatively high speed drive to platentransport 20, a double clutch 140 is provided on an intermediatetransfer shaft 142. As will be seen in FIG. 4, one side of clutch 140carries a forward drive gear 145 coupled to power take off shaft 103 bymeans of gear 148. The other side of clutch 140 carries reverse drivepulley 143 coupled to shaft 103 via toothed belt 144.

Output pulley 150 on shaft 142 is drivingly coupled by toothed belt 151with idler gear 152 on stub shaft 153. A second pulley 154 on shaft 153is coupled by toothed belt 155 with pulley 156 on shaft 157 of platentransport roll 231. Gear 158 on stub shaft 153 meshes with gear 159 ofone-way clutch 160 on shaft 115 of lower intermediate transport roll 18.One-way clutch 160 functions to drivingly connect shaft 115 and lowerintermediate transport rolls 16 with transfer shaft 142 whenever clutch140 is engaged in the forward document feeding direction to provide highspeed drive to roll pair 18, 19. On engagement of clutch 140 in thereverse feeding direction, clutch 160 disengages to prevent reverserotation of intermediate transport roll pair 18, 19. The upperintermediate transfer roll 19 is supported on idler shaft 161 suitablyjournaled in frame 36.

The drive ratios between shaft 103 and the pulley and gear input toclutch 140 are chosen to operate platen transport 20 at a relativelyhigher speed than that of primary feed roll 14. Since the lowerintermediate feed roll 18 is subject to both high and low speed driveinput, overrunning clutch 114 additionally serves to accommodateoverrunning of roll 18 when both clutches 105 and 140 are simultaneouslyengaged.

In summary, high speed drive from motor 100 is conducted by clutch 140in either the forward or reverse direction to platen transport 20. Whereclutch 140 is engaged in the forward direction, intermediate feed rollpair 18, 19 are turned at high speed.

Referring particularly to FIG. 4, to operate register edge 22 anddeflector 21, power takeoff shaft 103 is drivingly connected by belt 166with a cross shaft 167. Cross shaft 167 is in turn drivingly connectedby belt 169 with the input side of a one-half revolution clutch 170.Clutch 170, which is controlled by a suitable solenoid operator,functions when actuated to turn clutch output shaft 172 throughapproximately a half revolution as will appear. As seen in FIG. 7, cam173 on shaft 172 in turn works against follower 210 to move the registeredge 22 forward onto platen 6 or backwards off of platen 6. At the sametime, deflector 21 is either raised or lowered in response to movementof register edge 22 as will appear hereinafter.

Bail clutch 180 has an input gear 183 drivingly connected by belt 184with stub shaft 186. Gear 187 on shaft 186 is driven from reverse drivegear 145 through suitable intermediate gears (not shown) designed todrive belt 184 at the proper speed and in the proper direction. Clutch180 comprises a suitable solenoid actuated one revolution clutcheffective when engaged to turn crank arms 84 through one revolution andthereby reset bail 32.

Referring particularly to FIGS. 7 and 8 of the drawings, documentregister 22 comprises an elongated plate-like part presenting asubstantially square registration edge 202 facing platen 6. The width ofregister 22 is slightly greater than the width of platen 6. Register 22,when viewed in cross section, is slightly concave to conform to thegeneral shape of the platen supporting structure 204. As will appear,edge 202 of register 22 rides up and down on the supporting structure204 onto and off of the platen 6.

Register 22 is secured to lower support 205. A mounting rod 206 onsupport 205 is slidably journaled in block 208 which in turn isrotatably mounted on shaft 172 to provide the requisite up and downswinging motion of register 22 about cam shaft 172. A generally U-shapedcam follower 210 is secured to one end of rod 206. Bearings 211 onfollower 210 straddle cam 173 such that rotation of cam 173 movesfollower 210 together with rod 206 and register 22 back and forth.Spring 214 maintains register 22 against platen 6.

As described heretofore, rotation of cam shaft 172 is controlled byclutch 171, each engagement of clutch 17l serving to rotate shaft 172and cam 173 through approximately a one-half cycle to advance or retractregister 22 onto or off of platen 6.

Return document deflector 21 consists of an elongated plate-like partpivotally supported from the sides of return transport sub-frame 36"above register 22 such that the forward or leading edge 221 thereof isopposite register 22. Deflector 21 is mounted so that the upper orguiding surface 21' of deflector 21 is in operative alignment with thenip formed by the first return transport roll pair 23. Springs 224 biasreflector 21 downwardly toward register 22 therebelow.

To provide positive raising and lowering movement of deflector 21 intimed relationship with advance and retraction of register 22, register22 carries a pair of cam-like projections 225 at each outboard endthereof. Cams 225 are disposed to cooperate with deflector 21 so that,with movement of register 22 forward onto platen 6, projections 225raise edge 221 of deflector 21 to a position above the surface ofregister 22. This in turn provides a throat-like passage or opening 226through which the documents may pass unimpeded onto the platen 6.

On retraction of register 22, cams 225 are moved out from underdeflector 21 allowing the leading edge 221 thereof to drop into contactwith the upper surface of register 22 and closing the document passage226. The document leaving platen 6 is accordingly routed upwardly bydeflector 21 into the nip of first return roll pair 23.

Referring particularly to FIGS. 2, 4, 9 and 10 of the drawings, platentransport 20 consists of an endless flexible belt 230, the outer surfaceof which is light reflective. One such belt construction is disclosed inU.S. Pat. No. 3,482,676 to G.E. Fackler.

Platen belt 230 is stretched about drive and idler roll pair 231, 232respectively, rolls 231, 232 being arranged on opposite sides of platen6 with the axis of roll 231 being above register 22 while that of roll232 is above the far side of platen 6. Roll shafts 157, 158 arerotatably supported in sides 235, 236 of platen transport 20, sides 235,236 cooperating with rolls 231, 232 to form a unitary transportsub-assembly. Power shaft 157 is extended in length, the ends thereofbeing journaled in supports 238 secured on frame 36. This arrangementpermits the platen transport 20 to be swung as an assembly about theaxis of shaft 157 when single document copying is desired or forservicing platen 6.

Power shaft 157 carries pulley 156 which is drivingly connected to motor100 through forward and reverse clutch 140 as described heretofore.Sides 235, 236 each carry a projection 239 adjacent idler roll 232cooperable with upstanding spring locks 240 on the platen supportingstructure 204 to releasably retain platen 20 in closed position.Adjustable stops 241 are provided to limit downward movement of theplaten transport. Suitable safety means, exemplified by switch 309 inFIG. 9, is provided to sense disposition of platen transport 20 in theclosed and operative position. Switch 309 serves to prevent operation ofthe document handler 10 whenever platen transport 20 is raised.

The dimension and mounting of the belt supporting roll pair 231, 232 insides 235, 236 is such that the surface of platen transport belt 230therearound is spaced slightly above the level of platen 6 as seen inFIG. 9. An internal pressure roll 242 is provided, roll 242 engagingbelt 230 proximate the inlet to platen 6 and slightly downstream of theforward or operating position of register 22. Roll 242 is rotatablysupported by end arms 243 which in turn are pivotally carried from crossshaft 244. Shaft 244 is supported by sides 235, 236. Springs 245 biasarms 243 and pressure roll 242 downwardly such that roll 242 forces theportion of belt 230 opposite thereto against platen 6. As a result, aline-like portion of the platen transport belt 230 adjoining register 22normally rides against the surface of platen 6 to assure driving contactof belt 230 with the documents and engagement of the document edge withregister 22. The adjoining portions of platen belt 230 slope upwardlyaway from platen 6 to reduce or minimize frictional drag between thebelt 230 and the surface of platen 6. This in turn not only reducespower requirements but also the tendency of static electric charges tobuild up on the documents.

In FIG. 13 of the drawings, a control arrangement for the documenthandler 10 is there schematically shown. In that arrangement, a suitablecontroller 301 is provided to integrate operation of the variouscomponents of the document handler with each other and with theapparatus with which document handler 10 is used such as copyingapparatus 5. To provide the requisite timing intervals controller 301includes a suitable timing or counting device (not shown) driven bymeans of clock disc 302 on power transfer shaft 103, there being asuitable signal generator here shown as photocell 304, and light source305 disposed on opposite sides of disc 302. Note FIG. 4. Apertures 303in disc 302 permit light from light source 305 to intermittently strikephotocell 304 as disc 302 rotates to provide a clock-like input pulse.

Starting and stopping of document handler motor 100 may be convenientlyeffected by means of a suitable manually operated start-stop control308. In the arrangement shown, operation of the document handler 10 isdependent upon enabling signals from copying machine 5, tray coversafety switch 80 and platen transport safety switch 309, respectively.Switches 80, 309 reflect disposition of tray cover 60 and platentransport 20 in their closed operating positions. It is understood thatother contingency controls may be provided.

In operation, and referring particularly to FIGS. 1, 4 and 13, thedocuments 7 to be copied are placed in tray assembly 30 trailing edgedown, the document or documents resting atop bail 32. It is understoodthat receptacles 41, 41' are adjusted for proper document size.

With stop-start control 308 actuated and platen transport 20 lowered,closing cover 60 starts document handler motor 100. It is understoodthat return transport roll pairs 23, 27, 28, which are directly coupledto motor 100, are driven whenever motor 100 is energized. Further, latchsolenoid 79 is energized to engage latch mechanism 75 and lock cover 60in closed position.

At start-up, detector 88 on bail 32 signals the absence of documentstherebelow. In response thereto, controller 301 engages bail clutch 180to move bail 32 through one cycle from a position below the documents intray 12 to a position on top of the documents in the manner explainedheretofore.

With bail 32 properly positioned atop the documents 7 in tray assembly30, controller 301, in response to the document demand signal of waitstation detector 312 at the entrance to platen 6, actuates clutch 105 todrivingly couple primary feed roll 14, retard roll pair 16, 17 andintermediate feed roll pair 18, 19 with motor 100. Rotation of feed roll14 advances the bottommost document in tray 12 forward through retardroll pair 16, 17 which guard against feeding of double sheets, and intothe nip of intermediate roll pair 18, 19 operating at low speed.

As the leading edge of the first document moves out of roll pair 18, 19and comes opposite detector 312, controller 301 actuates clutch 140 tocouple gear 145 to drive shaft 142 and thereby operate intermediate feedroll pair 18, 19 and platen transport 20 in the forward direction toadvance the waiting document onto platen 6. It is understood thatengagement of clutch 140 in the document forward feed direction drivesintermediate feed roll pair 18, 19 at high speed, overrunning clutch 114accommodating the difference in driving input speed in the event primaryfeed clutch 140 is engaged.

Following a predetermined interval sufficient to allow the trailing edgeof the document to pass over and slightly beyond the register 22,controller 301 switches clutch 140 from forward to reverse drive, thelatter coupling drive pulley 143 with shaft 142.

Platen transport 20 is therefore reversed and the document movedbackwards on platen 6 until the rear or trailing edge thereof abutsagainst register 22. Abutment of the document edge with the edge 204 ofregister 22 locates the document in predetermined copying position. Withdocument movement prevented by register 22, belt 20 slides across thedocument surface until clutch 140 is disengaged. It is understood thatone-way clutch 160 prevents reversing of intermediate feed roll pair 18,19 upon reversing of platen transport 20.

Platen transport 20 is operated in reverse by controller 301 for aninterval sufficient to allow transport 20 to bring the document trailingedge against register 22, at which point clutch 140 is disengaged andplaten transport 20 stopped. With the document in copying position,copying apparatus 5 is then enabled to begin the copying cycle.

As the trailing edge of the first document moves past wait stationdetector 312, controller 301 again engages clutch 105 in response to thedemand signal from detector 312. Rolls 14; 16, 17; and 18, 19 aretherefore operated to bring the next or second document forward asexplained heretofore. When the leading edge of that document reachesdetector 312, controller 301 disengages clutch 105 to prevent feeding ofanother document. At this point therefore, the first document is incopying position on platen 6 while the second document is in a waitingposition adjoining the inlet to platen 6.

On completion of the copying cycle, controller 301 actuates registerdrive clutch 170 to retract register 22 and lower deflector 21. Whenretraction of register 22 and lowering of deflector 21 has beencompleted, controller 30 actuates clutch 140 in the reverse drive modeto couple belt 144 with shaft 142. Platen transport 20 is thereforedriven in reverse to move the document off platen 6. As the documentmoves off of the platen, deflector 21 routes the document into the nipof first return transport roll pair 23. Roll pair 23 cooperate withreturn guides 26 and roll pairs 27, 28 to carry the document back totray 12 where the document is deposited into receptacles 41, 41' atopbail 32.

As the trailing edge of the returning document passes a return documentdetector 315, controller 301 actuates register drive clutch 170 to bringregister 22 forward to registering position on platen 6. At the sametime, deflector 21 is raised. With register 22 in position, controller301 actuates clutch 140 in the forward drive mode to couple gear 145with shaft 142 and operate intermediate feed roll pair 18, 19 and platentransport 20 in the document feeding direction at high speed. Actuationof feed roll pair 18, 19 and transport 20 moves the waiting documentonto platen 6 and into registered position as described heretofore. And,with advance of the next document forward from the waiting station,controller 301, in response to the demand signal from detector 312,engages clutch 105 to bring the next document forward from tray assembly30 into waiting position as described.

The aforedescribed cycle of operation continues until the last documentis fed from under bail 32. On that event, controller 301, in response toa signal from the document detector 88 on bail 32, engages clutch 180 toreset bail 32 as described.

At this point, the last of the documents originally placed in trayassembly 30 is normally at the waiting station defined by detector 312.If bail 32 is to be restored to its original position atop the lastdocument of the document supply, the bail must be reset again after thelast document is returned to the tray assembly 30. To effectuate this,controller 301, on a last document signal from copying machine 5 andfollowing the elapse of a predetermined time interval adequate to allowthe last document to reach tray assembly 30, again actuates bail clutch180 to reset bail 32.

In cases where a single document cycle is desired, resetting of bail 32may be omitted to facilitate removal of the documents from tray 12.Similarly, resetting of bail 32 may be omitted on the last cycle of amultiple copy cycle for this purpose.

While the invention has been described with reference to the structuredisclosed, it is not confined to the details set forth, but is intendedto cover such modifications or changes as may come within the scope ofthe following claims.

What is claimed is:
 1. In a document handling apparatus for bringingdocuments into copying position on the platen of a document copyingmachine, the combination of:a flexible document transport belt; a pairof interior support rolls about which said belt is operatively disposed,said support rolls being spaced apart whereby to provide in cooperationwith said transport belt a belt operating run opposite to and extendingacross at least a portion of said platen; means for rotatably supportingeach of said rolls so that the surface of said transport belttherearound is spaced slightly above the plane of said platen wherebysaid belt operating run would ordinarily be spaced above and out ofdocument driving relationship with said platen; and internal pressuremeans adapted to force a line portion of said belt operating rundownward toward said platen into document driving relationship with saidplaten.
 2. The apparatus according to claim 1 in which said internalpressure means includes a pressure roll interiorly of said beltengageable with the inside wall of said belt operating run.
 3. Theapparatus according to claim 1 in which said internal pressure meansincludes spring means to bias said pressure roll toward said platen. 4.In an apparatus for supporting a document transport belt of an automaticdocument handling device adapted for use with a copying machine having arelatively flat platen surface on which the document to be copied ispositioned for copying purposes, the combination of:internal rollermeans for supporting said belt therearound such that an operating run ofsaid belt is stretched across said platen surface, said roller meansincluding at least one belt support roller adjacent the side boundariesof said platen surface with said belt operating run extendingtherebetween across said platen surface; means for rotatably supportingeach of said belt rollers in substantially parallel relationship suchthat the surface of said belt riding against the periphery of saidrollers is spaced slightly above the plane of said platen surface; andat least one pressure roller disposed opposite said platen surfacebetween said support rollers for contact with said belt operating run toforce the portion of said belt riding thereagainst downwardly towardsaid platen surface and into document driving engagement therewith, theaxis of said pressure roll being substantially parallel with the axes ofsaid belt support rollers.
 5. The apparatus according to claim 4 inwhich said copying machine includes abutment means raised above theplane of said platen surface against which an edge of the document to becopied is engaged whereby to register the document in position on theplaten surface, said abutment means being disposed between said beltsupport rollers;said pressure roller being spaced adjacent said abutmentmeans to assure engagement of the document edge with said abutmentmeans.